Medical instrument



Oct. 30, 1934. A. LANDAU MEDICAL INSTRUMENT Filed Nov. 2. 1929 19 of the patient.

Patenta& Oct. 30, 1934 i signbr to `the firm,

Elektricitatsgesellsclaft Sanitas m. `b H.Berlin, Germany Application member-2, 19292. Serial No; 404332'` In Germany'october 8, 1927 My` nvention relates'tormedical instruments and more particularly to instruments designed for the application of high frequency Currents. `It is an object of myj invention` to provide 5 means whereby sparking `at the body of the patient is eliminated. `To this'end .Iso design my instrument that the circuit for the electric current` is completed only after contacthas been 'established between the instrument and the body It is another object of my invention to avoid electric reactions on the body of the operator. To this end I provide aiseparate circuit in connection with a relay,` and Iconnect the circuit =ll of the relay with the handle of the instrument so that in case of anyleakage only the com paratively weak current of the relay circuit and not the strong current of i the line circuit,` will flow through the body of the operator.

u In the drawing aflixed to this specification-and Eig is a diagram showinga relay the circuit of which is shunted from the line wire A Fig.- 4 is a diagram showing a me operated relay,

QFig; 5 .is a ,diagram showing an instrument anically having a relay in a battery circuit as in Fig."2,

but with a modified arrangement of the blade,

and i t v 4 Fig. 6 is a diagram showing'an instrument in which thelcircuit of the relay is completed through the body of the patient.

Referring now 'to 'the drawing andtfirst to Fig. 1, 1 is a. casing of insulatingmaterial which' atits front end is provided with a loop or guide 2.` 'The guide i's gfrooved for the reception of the handle with an eye "7 which handleis iitted to slide in the casing 1 5 ,is the opposite electrode which is seated on the threaddend &of the handle' 4, `13 is an -insulated or insulatingbush on the electrode which; serves asan abutment for a spring 6, 14 is the matng bush; at the other end of the spring& Qisa slide secured to the inner end of theblade or electrode 3; 10 isj a conductor` in the slides, 15 is` a conductorlwhich is connected with a contact spring lz the contact blade ,3, which one ;of the, electrodes. 4 is'. a.

spring sliding on the electrode with 'its' end 16, 17 is a contact spring at the end of the electrode 5 which together with a reduced projection 18 at the end of the electrode, makes a sort of clamp or seat furthe pointed end of the conductor 10, and 11 is a shoulder at the inner end of the slide '7 which,` when' the circuit is closedat'lo, 17, '18, is engaged by the end of the spring' 16, breaks the circuit and holds the slide in' position. Another conductor, not shown, is provided for carrying away the current from the electrode 3. The handle 4 is of ,insulating material as shown but obviously might' be of 'conducting material, t 'and insulated from the electrode 5.

In operation, the instrument is placed on a part of the patient's'body, for instance a tonsil; and thenpressureis applied on'thehandle 7topush the electrode 5 toward the point of the' conductor 10. It will be understood that the blade 3 is advanced freely' until it\ contacts with the tonsil and thereupon an increasing' pressure reacticn is exerted on the spring 6. but stillthe circuit is not closed so that the electrode 3 is applied without sparking. O nlyafter the spring 6. has beencompressed to such an extent that the circuit is closed at '17 and 18, current fiows in the' electrode, while the blade` 3 still'advances for separating the tonsil. When the blade has been advanced so far that the end 1`6 of spring 12 ergages behind the shoulder l1` of the slide 4 the circuit 's broken and remains in this condition until theslideis'released ,byturning it through about 90 degrees. In this manrier, sparking at the body of the patientwhen removing the instrument is also eliminated 'as the slide 4 will only be released after the instrument hasbeen retracted from the body of the patient.

In the operation' of the instrument as described, it is seenthatthe spring 6 and the electric switch, comprising'the contact elements 17,

18 and the pointed end of the conductor 10, act as means for temporarily preventing flow of diathermic current when thetool or blade 3 is in its initial position prior to an operative stroke and for permitting flow of said current through a patient's. body during such operative stroke; said means being operatedby and substantiallysimultaneously with contact of said tool 'with said patient's body The spring 12 cooperating with 'shoulder 11 acts as means for breaking thediathermic current at the conclusion of an operative stroke without independent manipulation; that 'is breaking of the current occurs as an incident of the perating stroke;

In this, the simplest form of the instrument, sparking at the blade 3 is avoided at the beginning and at the end of the operation but still there is the risk of injury to the operator through leakage from the electrode 5. This is avoided in the several arrangements the diagrams of which are illustrated in Figs. 2-6.

Referring first to Fig. 2, the electrodes 3 and 5, with the spring 6 between them, are indicated only diagrammatically. The body of the patient, a tonsil as assumed in the present instance, is in-, dicated by the sectioned area 19, 20 arethe line wires of a system, 21 is a diathermic apparatus of any suitable kind, 22 and 23 are wires extending from the apparatus to the blade -3 and the tonsil 19, respectively, 24 is a battery, 26 is a relay in the diathermic apparatus', and 27,28 are the wires of the relay-and-battery circuit.

It will be understood that when the electrodes 3 and .5 get into contact, as described with reference to Fig. l, the circuit 27, 28 of the relay 26 is closed and the relay outs in the circuit 22, 23 through the blade 3 and the body of the patient. Here, sparking is also avoided because the' circuit of the relay 26, and consequently the circuit 22, 23 can only be closed after the electrode 3 has come into contact with the body of the patient but, in addition, the operator is protected against the strong current from the system Referring now to Fig. 3, the arrangement is the same as described with reference to Fig. 2, with the exception that the circuit of the relay 26 is constituted by a shunt 29, 30 from the system 20.

Referrng now to Fig. 4, the relay 26 is here operated mechanically through the medium of a fiexiblebar 31 which is attached to the electrode 5 and is fitted to slide in a fiexible tube 32 which is Secured at one end to the electrode 3.

Referring now to Fig. 5, this illustrates an apparatus in which the electrode 5 is not pushed but pulled as indicated by the arrow. The spring 6 is inserted between an extension 25 of the electrode 5, and an extension 33 at the end of the blade or electrode 3, 'which in the present instance is designed like the loop 2, Fig. 1; with an opening 34. The blade 3 is placed on the tonsil 19 so as to engage it with the closed end of the loop 34, and a pull is exerted at the end of the electrode 5 until the .extensions 25 and 33 make contact, closing the circuit of the battery 24 and the relay 26. otherwise, the operation is the same as that described with reference to Fig. 2.

Referringnow to Fig. 6, the blade 3 is the single electrode, the electrode 5 having been omitted, and the blade 3 is directly engaged by a handle or the like, not shown, so as to push it toward the tonsil 19. The battery 24 is connected through the wire 27 with an 'electrode 35 which engages the tonsil 19. The wire 28 extends from the blade 3 to the relay 26 as described', a wire 36 connecting the battery 24 with the relay 26. The wire 22 is connected with the blade 3, and the wire 23 is connected with another electrode 37 which is also adapted to be placed in contact with the tonsil 19. It will appear that when the blade 3 is placed in contact at 19 the circuit of the relay 26 is closed'through 3, 23, 36, 24 and 27, whereupon the relay. makes the circuit 22, 23 which is completed through the body of the patient at 19.

In the systems having a battery 24 in the relay circuit, thebattery might be replaced by a transformer, not shown, the primary coil of which is connected with the system so that the secondary Supplies only low-voltage current` to the instrument. The transformer should not'be grounded.

In this manner' an additional safety factor for the patient and for the operator is obtained.

I wish it to be understood that I do not desire to be limited to the exact details of Construction shown and described for obvious modifications will occur to a person skilled in the art.

In the claims affixed to this specificaton no selection of any particular modification of the invention is intended to the exclusion of other modifications thereof and the right to subsequently make claim to any modification not covered by these claims is expressly reserved.

I claim;-

1. A medical. instrument fed with high frequency current comprising a casing, a blade fitted to slide in said casing, an electrode also fitted to slide in said casing so as to make contact with said blade, resilient means inserted between said blade and said electrode so as to make up a mechanical connection of said blade with said electrode and to advance said blade before contact is made between it and 'said electrode, a contact spring fitted to slide on said electrode, an insulated handle on said electrode, a shoulder on said handle adapted to be engaged and retained by said contact spring, and a circuit connected to said blade and said contact spring.

2. A medical instrument fed with high frequency current comprising a casing, a blade fitted to slide in said casing, an electrode also fitted to slide in said casing so as to make contact with said blade, resilient means inserted between said blade and said electrode so as to make up a mechanical connection of said blade with said electrode and to advance said blade before contact is made between it and said electrode, a contact spring fitted' to slide on said electrode, an insulating handle on said electrode, a shoulder on said handle adapted to be engaged and retained by said contact spring, and a circuit connected to said blade and said contact spring.

3. 'A medical instrument fed with high frequency current comprising an Operating tool, a circuit for supplying heating current to said tool, means for pushing said tool into contact with the body of the patient, a resilient part inserted between said pushing means and said tool, and a switch in said circuit adapted to be operated by the reaction of the patient s body and to complete said circuit after contact has been made at the body of the patient. i 4. 'A medical instrument fed with high frequency current comprising an Operating tool, a circuit for supplying heating current to said tool, means for pulling said tool into contact with the body of the patient, a resilient part inserted be'- tween said pulling means and said tool, and a switch in said circuit adapted to be operated by the reaction of the patient's body and to complete said circuit after contact has been made at the body of the patient.

5. A medical instrument fed with high frequency current comprising a casing, a tool fitted to slide in said casing, a tool Operating element also fitted to slide in said casing' and normally spaced from said tool; the said tool Operating element being adapted to approach and to operate 'said tool during an operative stroke of saidinstrument; and means cooperating with at 'least one of said tool and said tool Operating elements for commencing the flow of said diathermic current upon approach of said tool Operating element to said tool during an operative stroke of said instrument; said means being operable by said operative stroke.

6. The combination of claim 5 wherein said means comprises an electric switch having at least two contact elements, a source of diathermic current attached to one of said elements and means for holding said elements apart prior to said operative stroke and for permitting closure of said elements during said stroke.

7. The combination of claim 5 wherein said means comprises an electric switch having at least two contact elements and a resilient means for holding said elements apart prior to an operative stroke of said tool and for permitting closure of said elements during said operative stroke, whereby flow of said diathermc current is commenced. 

